A cell surface antigen that cross-reacts with My4, a monoclonal antibody to CD14, is expressed on human monoblastic cell line U937, B-lymphoma cells, and polymorphonuclear leukocytes.
The CD14 antigen was originally identified on monocytes as a differentiation marker and usually detected by a panel of monoclonal antibodies, including My4 and LeuM3. Recent studies have shown that CD14 antigen is expressed on Langerhans cells, a subject of normal B-lymphocytes, neutrophils, and subtypes of B-cell non-Hodgkin's lymphomas. These antigens, however, react with My4, but not with LeuM3, and the reason for this has not been elucidated. In this study, we found that similar My4+/LeuM3- epitopes are expressed on the human monoblastic cell line, U937. Northern blotting demonstrated that the U937 cells express neither 1.4 kb CD14 transcripts nor possible alternative spliced forms of CD14 transcripts. The molecule was resistant to phosphatidylinositol specific phospholipase C, which effectively hydrolyzes glycosyl-phosphatidylinositol anchored protein, decay accelerating factor, on the same cells. Lipopolysaccharide, which down-regulates the expression of CD14 on monocytes, did not alter the expression of the molecule. We concluded that the My4+/LeuM3- molecule on U937 cells is not CD14 antigen but another surface protein. A similar molecule was also detected on B-lymphoma cells from a patient with non-Hodgkin's lymphoma and on polymorphonuclear leukocytes from healthy donors.
Ikemoto
T
T
Central Clinical Laboratory, Osaka Medical College, Takatsuki, Japan.
Nakagawa
T
T
Hatanaka
M
M
Hasegawa
M
M
Kageyama
T
T
Hirano
M
M
Shimizu
A
A
D000911:Antibodies, Monoclonal; D000954:Antigens, Surface / Q000187:drug effects / Q000276:immunology*; D003429:Cross Reactions; D000939:Epitopes; D005455:Fluorescent Antibody Technique; D006801:Humans; D018950:Lipopolysaccharide Receptors / Q000235:genetics / Q000276:immunology*; D008070:Lipopolysaccharides / Q000494:pharmacology; D016393:Lymphoma, B-Cell / Q000276:immunology*; D009000:Monocytes / Q000276:immunology; D009504:Neutrophils / Q000276:immunology*; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D054801:Phosphoinositide Phospholipase C; D012333:RNA, Messenger / Q000032:analysis; D014407:Tumor Cells, Cultured; D010738:Type C Phospholipases / Q000494:pharmacology
D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D000939:Epitopes; D018950:Lipopolysaccharide Receptors; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D010738:Type C Phospholipases; D054801:Phosphoinositide Phospholipase C; D043265:Phosphatidylinositol Diacylglycerol-Lyase